Process of purifying and adding a green fluorescence to lubricating oil



Patented Apr. 9, 1929.

UNITED STATES PATENT OFFICE.

wmr 1). RIAL, or WATSON, AND wnr'rrom) R. BARRATT, or rALosvERnEs ns'ra'rns,

CALIFORNIA, ASSIGNORS "IO PAN AMERICAN PETROLEUM COMPANY, OF LOS ANGELES, CALIFORNIA, A CORPORATIONOF CALIFORNIA.

PROCESS. OF PURIFYING AND ADDING A GREEN FLUORESCENCE LUBRICATING' OIL.

No Drawing.

This invention relates to a method of neutral1z1ng,-1mpart1ng a green fluorescence,

clarifying, and improving the color of lubri- .a method of clarifying, improving the color and imparting a desired fluorescence to anoil. In that pending application the process involvesmixing coal tar pitch and a decolorizing clay with a lubricating oil stock, then heating the same in a commingled state at a suitable temperature for obtaining the desired fluorescence. and color, and thereafter separating the oil from the decoloriz- 'ing clay,'adsorbed constituents, and coal tar residue.

We have discovered method produces asatisfactory product, the decolorizing clay cannot be commercially revivified. for re-use, and also that a smaller quantity of the decolorizing day may be employed by our improved method for Ohtaining the desired color and fluorescence of a lubricating oil stock.

An object of the invention is'to provide a method or process whereby a substantially uniform clarified oil of the desired color and fluorescence may be produced with a minimum consumption ofthe clarifying and decolorizing agent; another object is to provide such a process that the decolorizing agent may be recovered 'for re-use and the process conducted with a minimum consumption of time. 1

The process of this application consists broadly. first in the separation of lubricat- 0 ing oil from crude petroleum oil by a distillation operation, preferably under a reduced pressure less than atmospheric, then immediately treating the separated lubricating oil stock at an elevated temperature under steam pressure with a solution of caustic potash as tion of John C. Black and Wirt D. Rial, Serial No. 187,110, filed April 27, 1927. The lubricating oil stock after this treatment is 0 then treated with sulfuric acid by welllmown methods followed by treatment with an adsorbent clay to substantially completely remove the acid reaction products as out described in the pending applica Which may or may not'have Application filed June 7, 1927. Serial No. 197,225.

lined in United States patent of James W. \Veir, No. 1,564,501.

After these treatments the lubricating oil stock is re-distilled, preferably under a pressure less than atmospheric, to separate therefrom the heavier cylinder lubricating oil stock from the relatively lighter grades of lubricating stock, known in refinery practice as overhead stock. The overhead stock which may be any desired grade, is commingled with a mixture of coal tar and lime, preferably hydrated lime, after which the commingled products are heated to approximately a temperature of 250 F. and then lime employed isapproximately 1% per cent coal tar pitch and of a pound of lime (Ca(O1 per gallon of oil treated. After i separating the lime and residual coal tar that while that pitch from the treated lubricating oil stock, preferably by a filteration operation, the oil is clarified and decolorized with a decolorizing clay at temperatures ranging from 230 to 320 F. or a little higher. The amount 'of coal tar pitch may vary from as low as to as high as 5 per cent by weight of the oil treated, this variation depending upon the stock treated and the product desired.

In case it is desired to obtain a more intense green fluorescence to the lubricating oil stock, a greater percentage of the coal tar is employed in accordance with the fluorescence desired, and in which case a larger proportional percentage of lime may be employed in order to retain'the residual coal tar pitch, which may vary from of a pound to as high as 1 pound per gallon of oil to be treated.

As a specific example of a pitch which may be employed, a coal tar pitch made by the distillation of a coal tar may be given as an illustration. This pitch may be a reduced residue of varying viscosities, preferably however, a, pitch which does not contain hydrocarbons having boiling points less than the lubricating oil stock treated, is desired.

It is to be understood that any lubricating oil stock may be treated by this invention been treated by the methods heretofore described in this invention and that such invention consists principally in the combined treatment of a lubricating oil stock with lime, preferably filtered. The amount of coal tar pitch and calcium hydroxide and a coal tar residuum containing hydrocarbons having boiling point substantially not less than the lubrieating oil to be treated, that by such method the lubricating oil stock treated is rendered free of acid impurities as Well as imparting thereto a desired green fluorescence, this treatment being carried out preferably. at

temperatures substantially not less than 230 F. y

While the process herein described is Well adapted for carrying out the objects of the present invention, it is to be understood that various modifications and changes may be made Without departing from the spirit of the invention and the invention includes all changes and modifications as appear in the scope of the appended'claims.

We claim:

1. A process ofpurifying and impnoving.

the quality of lubricating oil containing acid constituents, comprising 1 commingling the lubricating oil witlr' calcium hydroxide and a coal tar pitch containing green fluorescent bodies at a temperature of substantially not less tha'n230 degrees F. in quantities suflicient to neutralize-and adsorb the acid constit-uents contained therein and add green fluorescent bodies to the lubricating oil and then separating the lubricating oil containing the green fluorescent bodies from the coal tar pitch residue, and excess calcium hydroxide containing the adsorbed constituents.

2. A process of purifying and improving the quality of lubricating-oil containing acid constituents comprising cominingling the lubricating oil with calcium hydroxide and a coal tar pitch containii-igl green fluorescent bodies at a temperature of'substantially not less than 230 degrees F., inquantities sulficient to neutralize and adsorb the acid con stituents contained therein and "add green fluorescent bodies to the lubricating oil and then separating the coal tar pitch residue and excess calcium hydroxide containing the adsorbed constituents from the lubricating oil containing the green fluorescent bodies, a

perature of substantially not less than 230 degrees F in quantities sufficient to neutralize and adsorb. the acid constituents con-- tained therein and add green fluorescent bodies to the lubricating oil and then separating the coal .tar pitch residue and excess calcium hydroxide containing the adsorbed calcium salts from the lubricating oil and green fluorescent bodies and finallyclarifying and decolorizing the lubricating oilto the required degree with a clarifying and decolorizing agent. I

4. A process of purifying, improving the quality and adding green fluorescent bodies to a lubricating oil containing acidconstituents, comprising commingling the lubricating oil withcalcium hydroxide and a coal.

tar pitch at a temperature of substantially not less than; 230 degrees F., in quantities suflicient to neutralize and adsorb the acid constituents contained therein and add green fluorescent bodies to the lubricating oil and thenjseparating the coal tar pitch residue and excess calcium hydroxide containing theadsorbed constituents from "the lubricating oil containing the green and finally clarifying and decolorizing the lubricating oil to the required degree with a clarifying and decolorizing agent.

tures.

s .WIRTD. RIAL.

\ WHITFORD R. BARBATT.

fluorescent bodies,

In testimonywhereof we aflix our signa- 

